remember biosphere? not the movie starring pauly shore, but the building that was supposed to simulate a self-sustaining mini earth in a space ship? turns out it failed and is slowly rotting. check out the pictures near the end of this article.
http://bldgblog.blogspot.com/2010/01/remnants-of-biosphere.html

more info at wikipedia:
http://en.wikipedia.org/wiki/Biosphere_2